The new PXIe-5665 RF VSA comes standard with 25MHz bandwidth but has an option for 50MHz. If the 25MHz option is purchased, is it possible to upgrade the bandwidth to 50MHz through software or do I need to replace the hardware. If I need to replace the hardware, do I have to buy a whole new 50MHz 5665 or can I just pay the delta and get the new module.
The bandwidth is going to be a hardware limitation, so you will need different hardware to upgrade to 50 MHz. To find out what kind of options you might have for upgrading or replacement, I recommend trying to contact your local Account Representative or Field Engineer. They should be able to let you know what the best option will be.